Rotary converter.



lV.A,FYNN. ROTARY QONVBRTER. APPLICATION FILED JUNE 12, 1911.

1,103,192. @mmm my 14,

2 SHEETS- SHEET 1.

V. A. PYNN.

ROTARY CONVERTER. APPLOA'ION FILED JUNE 12, 1911.

1 1 08, 1 92. Patented July 14, 1914.

Fig-.3.A

2 SHEETS-SHEET 2.

WIT/VESSES: INVENTOR Valre A.Fynn,

Ilm@ f B ,In URNEY along an axis at rightvangles to the brush 'line and will either help or oppose the magnetization due to the normal excitingwinding of the Converter. I counteract the distiirbing influence of these varying armature reactions preferably by disposing certain`series windings along the brush axis and at right 'angles toit.

windings is. so connected as to oppose the direct current 'armature reaction; the secondV factor ofthe converter are constant, but: due

to the alternating currents fed into the ar mature by way of the slip rings.

The auxiliary excita-tion I produce along thc brush line is likely to interfere with the commutation. To avoid this I produce a local and opposite magnetization covering thecommutating zone and of sufficient mag.- nitude to reduce the resulting magnetization in that spot to harmless proportions. small resultant magnetization may be left to assist commutation and the series winding disposed in this axis and intended to take care of the excess of direct current armature reaction may beso proportioned as to neu tralize the latter and provide a commutating field varying in strength with the direct current output.

My invention will be better understood by reference to. the accompanying diagrammatic drawings in which- Figure l vshows my invention as applied to a single phase converter. Fig. 2 shows a modificationy thereof ap lied to a rthreephase converter and Fig. indicates the pre ferred structure ofthe magnetic circuits of my improved converter, and also shows how the several windings of Fig. can be disposed on the rotor and stator. The way in which the various windings are indicated in this tigure is intended to merely distinguish these windings from each other and not to show the direction of currents.

Although the drawings all represent 2- pole converters it will be understood that the invention is applicable to converters with any number of pole pairs.

In describing Figs. l Aand Q itwill be convenient to simultaneously refer to the more detailed Fig. 3. Referringto Fig. l the revolving member of the converter carries a colninutcd winding Q connected to the slip rings 3 and -l, brushes 5-'G 'are shown as resting directlyv on said'winding. Brushes 7 and S connect the two slip rings tothe secondarjtT of the transformer l?, which is adjustable at 16, and the primary of which is connected to the alternate current mains The first of these series i8, 19. ,The commuted winding 2 is disposed in the slots 10 of the rotor 33 of Fifi. 3. The field structure carries a winding 20-21-22 short-circuited along a plurality of axes per pole pair. The normal unid1- rectional magnetization of the machine is produced by the winding 13v connected to the commutator brushes 5-6 by way of the regulating switch 14 coacting with the resistance 15. This normal exciting winding is preferably disposed along an axis disg placed by 90 electrical degrees from the axis of the 'brushes 5, 6. The auxiliary magnetization in Fig. 1 is produced by the auxiliary exciting winding 31 also connected in parallel to the commutator brushes and controlled bv the regulating switch 3l, eoacting with the resistance .X small commutating winding 32 located in the immediate neighborhood of the coil sides undergoing commutation is connected in series with the auxiliary exciting winding 3l and produces a magnetization co-axial with that o'tl and with the 'brush axis 5,' 6. The resistance 36 controlled 'by the switch 37 affords means for adjusting the magnitude of the magnetization produced by the commutating winding 89.. The disturbing effects of the armature reaction which set in as soon as the ratio'of the alternating current voltage t0 the direct current voltage is materially altered, are taken care of in Fig. 1 by the windings 38 and 43 connected in series relation with the commuted winding 2 and located between the brush 6 and the direct current main 25; Whereas the other direct current main 24.- is directly connected. to the brush For simplioitys sake I will refer to windings 38 and 43 as neutralizing windings.

The winding 38 is co-axially disposed with the brush line 6 and :is adapted to oppose the excess of direct current armature reac tion in that axis. Said excess appears as soon as an attempt is made to alter the voltage atie of the converter under load. The neutralizing winding 43 is displaced by 90 electrical degrees from the brush axis 5, 6 and is adapted to oppose that component of the alternate current armature reaction which appears along theaxis of 43y as soon as the voltage ratio of the converter is. varied. The magnetization produced by thewinding 38 can be adjusted by means of theresisb ance 4G connccted'in parallel to said windif .ing and controlled by the switch 454 The is desired to operate the machine yvith the normal voltage ratio then the circuit of the auxiliary exciting Winding 3l is lef-t open.

' The tvvo neutralizing` windings 38 and 43 are short-circuited bymean'sof the vsvvitches 47 and'27 and the normal unidirectional magnetization is adjusted by means of the switch 14 in such a manner as 'to secure the desired power factor on the alternate current side. If it is noW desired to reduce the direct current 'voltage then the exciting current in the normal exciting Winding 13 1s decreased by means of the switch 14 While the magnetization 'produced by the auxiliary` exciting winding- 31 is raised from its vetI zerol value-v to 'one which Will bring the totalvv magnetization back to approximately its original, value. -In addition-it is necessary to soposition switch 27 that the magnetization produced by the Winding 48 and Which,.of course, is always'proportional to the direct current output of the converter,v

Whether said Winding is shunted by the resistance 28 or not, isl equal and opposed to that component ofthe alternate 'current `armaturereaction which appears' along the a'xis ofthe Windingl 43 for the relative magnetization. chosen for the-shunt :excit-I ing windings 13 Aand 31.A It, is alsolnelceslsary to so laceswitch 47 that the magneti'- 1 'zation pro uced'by' the winding-38 'becomes practically equal and opposedto theV difv-ei'encefo'f the direct currentarmature reaction andthe alternate current armature reaction along the'axis ofthe.` brushes 5, 6. It is-'clea'r that'ifth'e 'windings'38 and 4 3j are to have'- no material influenceon the. direct current voltage ofthe converterth'e i. they magnitude of Vthe `ni'agnet'ization they .40

produce must-'be adjusted afresh each time the magnitudejfof .the magnetization 'produced by the shunt exciting windings 13 and 31 isaltered, but the 'adjustment "of 38 "and, .'43 can remain lunaltered irrespective oftheload onthe converter as long as. tliepadjiie't-"f 1 ment .of l13 'fand g ildis.' notl altered; v The tions 0f; theshorticircuited 205121. 'I ucture' al re'of .particd i olf4v single phaseconverters'.

rig; venana 'from uit prviens agua-'iii that thenauxiliary sh1nt' exciting-Winding .has been omitted, '.wh'le 'the` ommutating p `vvindinggf"32de"connectedv inv 'series with the '-fneutralizin Wi1 1din`gs instead of the shunt'auxiliary fvvil1-di'ng. The arrangement shown p in ythis ligure is adapted to yield a voltage ratio which: varies' considerably Withload-variations. 1,The-.general'rprinciples of I operationjare, Vihovv'evera videntical 'in both- Cases.

et 1 The function o f the commutating winding- 32 is to reduce the resultant magnetic flux in the commutating zone to such a value and direction as will assist rather than impair the commutation..

Fig. 3 clearly shows the relative space position on the stator and rotor of theseveral ,windings Which' have been particularly described With reference to Fig. 1.

Ivvish it to be understood that I do not 'limit myself' to the particular embodiment Winding displaced from the axis of the` brushes and connected in parallel thereto, an auxiliary yield Winding co-axial With the brushes, and also connected in parallel thereto, means for varying the axis of' the re- `sultant magnetization due to lthe exciting and auxiliary Awindings, a neutralizing winding co-axial with' and connected 'in series relation with the brushes', andimeans for varying the ampere turns of said neutralizing winding. 'A

'251.111 alrotary converter, thecombination with an armaturehaving slip-rings', a comf'mutator-and brushes on said commutator, of*

a field structure havinga normal exciting 'Winding displaced from the-axis' of the brushes and connected in .parallel thereto,l an auxiliary field winding'co-axial with the brushes and Ialsoconnected in parallel there- 'to,"means for' varyingtheaxis Aofthe resultiant magnetization due to :the exciting and j llal'lxiliary. windings, ytwo neutralizing windvings fconnectedfin; series lrelation vwith said brushes, one of said'windings being co-axial Awith the bitfshes and the.v other being disings.'

' 3.= In .a `rotary converter, the combination I placed therefronn''alid 'means for varying' the'alnpeeturns of said neutralizing windan'armaturehaving slip-rings, a com- 'mutat'or end brushes-'on sald commutator, of

afield vstructure having anormal exciting 'winding displaced'- from the axis of the brushes,' an auxiliary" ield- AWinding lco-axial `with thebrushes; means for varying the axis of the resultant magnetization due to the exciting and auxiliary windings, a commutati'ng Winding'- co-axial with the auxiliary el'd Winding, and connected in series there- Withya neutralizing -Windingco-axial with 'the brushes and connected in series/relation thereto for producing a magnetization proportional-tothecurrent flowing through said iad brushes, and 4mleans'fer varying the ampere tunis of said neutralizing Winding.

4. 'In a rotary converter, the combination with an armature havingyslipfrings, a commutator and brusheson said commutator, of a field structure Without defined polar projectionsjand having a normal exciting Winding displaced from the axis of the' brushesjand connectedyin parallel thereto, an auxiliary field winding co-axial with the brushes, and also connected in parallel thereto, means for varying the axis of the resultant magnetization due to -the exciting and auxiliary windings, a neutralizing Winding co-axial with and connected in series l relation With the brushes, means for varying the ampere turns'of said neutralizing Winding, and a Winding shortecircuited along more than one axis per pole pair.

5. The method of adjustingr ,the relation betweenfthe magnitudes ofthe alternating current and direct current voltages of a rotary converter. having a commutator and brushes, which consists in producing a unidirectional exciting field and a neutralizing field displaced therefrom, varying the axis of the v,exciting field relatively to the brush axis, and simultaneously7 varying the magnitude of the neutralizing field.

6. The method of adjusting the relation between the magnitudes of the alternating current and direct currentvoltages or a rotary converter having a commutator and brushes, which consists in producing a unidirectional exciting field dependent on the terminal voltage on the direct current side and a neutralizing field displaced therefrom and dependent on the load current on the d'1- rect current side, varying the 4axis of the exciting field relatively to the brush axis, and simultaneously varying the axis of the neutralizing field and the number of turns produeing the same.

7. The method ot' adjusting the relation between the magnitude ofthe alternating current and direct current voltages of a rotary 'converter having a commutator, sliprings, brushes on the commutator, means for producing a unidirectional excitation independent ofthe load, and means for producing a neutralizing flux dependent on the load, which consists in simultaneously varying the axis of the exciting flux and the axis and magnitude of the neutralizing flux.

In testimony whereof, I have hereunto set my hand and affixed my seal in the presence of the -two subscribingr Witnesses.

'VALRE ALFRED FYNN, [La] lVitnesses lV. A. ALEXANDER, Enizan'rir BAILEY. 

